A top government department lawyer will give evidence on the unlawful robodebt scheme when the royal commission into the scheme resumes.

The second day of the final hearing block of the robodebt royal commission will hear from the former chief counsel for the Department of Social Services Paul Menzies-McVey.

Other witnesses scheduled for Tuesday include Services Australia’s compliance and debt operations officer Jeannie-Marie Blake and Attorney-General department’s assistant secretary Michael Johnson.

The commission is examining who knew about the legality of the scheme and how robodebt was implemented.

The final round of hearings, which began on Monday, is focusing on the inquiry by the commonwealth ombudsman into the scheme, proposals to expand robodebt, the impact it had on victims and how it was wound up.

The impact on victims and their families was the subject of much of Monday’s hearings, which heard from the mother of a robodebt victim, who committed suicide after receiving countless debt notices.

Jennifer Miller, whose son Rhys Cauzzo died in 2017, said the debt notice of more than $17,000 which was calculated using illegal averaging methods, exacerbated his previous mental health conditions.

She told the commission attempts to obtain information from government departments and relevant ministers were stonewalled.

“Not once did I get a truthful answer,” she said.

The correspondence also included letters to then human services minister Alan Tudge.

She said correspondence she received from Mr Tudge following Rhys’s death just contained platitudes.

The final block of hearings will run for three weeks, with the final report due at the end of June.

Commissioner Catherine Holmes last week wrote to the government requesting a two-month extension of the inquiry.

– AAP